Re: [PATCH v2 1/4] interconnect: qcom: icc-rpmh: Add QoS configuration support

From: Odelu Kukatla
Date: Thu Feb 22 2024 - 05:47:46 EST




On 2/5/2024 8:38 PM, Dmitry Baryshkov wrote:
> On Mon, 5 Feb 2024 at 16:57, Odelu Kukatla <quic_okukatla@xxxxxxxxxxx> wrote:
>>
>> It adds QoS support for QNOC device and includes support for
>> configuring priority, priority forward disable, urgency forwarding.
>> This helps in priortizing the traffic originating from different
>> interconnect masters at NoC(Network On Chip).
>>
>> Signed-off-by: Odelu Kukatla <quic_okukatla@xxxxxxxxxxx>
>> ---
>> drivers/interconnect/qcom/icc-rpmh.c | 161 ++++++++++++++++++++++++++-
>> drivers/interconnect/qcom/icc-rpmh.h | 32 ++++++
>> 2 files changed, 189 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/interconnect/qcom/icc-rpmh.c b/drivers/interconnect/qcom/icc-rpmh.c
>> index c1aa265c1f4e..67e600f1191d 100644
>> --- a/drivers/interconnect/qcom/icc-rpmh.c
>> +++ b/drivers/interconnect/qcom/icc-rpmh.c
>> @@ -1,28 +1,69 @@
>> // SPDX-License-Identifier: GPL-2.0
>> /*
>> * Copyright (c) 2020, The Linux Foundation. All rights reserved.
>> + * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved.
>> */
>>
>> +#include <linux/clk.h>
>> #include <linux/interconnect.h>
>> #include <linux/interconnect-provider.h>
>> #include <linux/module.h>
>> #include <linux/of.h>
>> #include <linux/of_platform.h>
>> #include <linux/slab.h>
>> +#include <linux/bits.h>
>>
>> #include "bcm-voter.h"
>> #include "icc-common.h"
>> #include "icc-rpmh.h"
>>
>> +/* QNOC QoS */
>> +#define QOSGEN_MAINCTL_LO(p, qp) (0x8 + (p->port_offsets[qp]))
>> +#define QOS_SLV_URG_MSG_EN_MASK BIT_MASK(3)
>> +#define QOS_DFLT_PRIO_MASK GENMASK(6, 4)
>> +#define QOS_DISABLE_MASK BIT_MASK(24)
>> +
>> +/**
>> + * qcom_icc_set_qos - initialize static QoS configurations
>> + * @qp: qcom icc provider to which @node belongs
>> + * @node: qcom icc node to operate on
>> + */
>> +static void qcom_icc_set_qos(struct qcom_icc_provider *qp,
>> + struct qcom_icc_node *node)
>> +{
>> + const struct qcom_icc_qosbox *qos = node->qosbox;
>> + int port;
>> +
>> + if (!qp->regmap)
>> + return;
>> +
>> + if (!qos)
>> + return;
>> +
>> + for (port = 0; port < qos->num_ports; port++) {
>> + regmap_update_bits(qp->regmap, QOSGEN_MAINCTL_LO(qos, port),
>> + QOS_DISABLE_MASK,
>> + FIELD_PREP(QOS_DISABLE_MASK, qos->prio_fwd_disable));
>> +
>> + regmap_update_bits(qp->regmap, QOSGEN_MAINCTL_LO(qos, port),
>> + QOS_DFLT_PRIO_MASK,
>> + FIELD_PREP(QOS_DFLT_PRIO_MASK, qos->prio));
>> +
>> + regmap_update_bits(qp->regmap, QOSGEN_MAINCTL_LO(qos, port),
>> + QOS_SLV_URG_MSG_EN_MASK,
>> + FIELD_PREP(QOS_SLV_URG_MSG_EN_MASK, qos->urg_fwd));
>> + }
>> +}
>> +
>> /**
>> * qcom_icc_pre_aggregate - cleans up stale values from prior icc_set
>> * @node: icc node to operate on
>> */
>> void qcom_icc_pre_aggregate(struct icc_node *node)
>> {
>> - size_t i;
>> - struct qcom_icc_node *qn;
>> struct qcom_icc_provider *qp;
>> + struct qcom_icc_node *qn;
>> + size_t i;
>>
>> qn = node->data;
>> qp = to_qcom_provider(node->provider);
>> @@ -49,8 +90,8 @@ EXPORT_SYMBOL_GPL(qcom_icc_pre_aggregate);
>> int qcom_icc_aggregate(struct icc_node *node, u32 tag, u32 avg_bw,
>> u32 peak_bw, u32 *agg_avg, u32 *agg_peak)
>> {
>> - size_t i;
>> struct qcom_icc_node *qn;
>> + size_t i;
>
> Please abstain from making the cleanup changes in the same patch as
> the functional changes. These changes either should be dropped or
> moved to a separate patch.
>

Sure, i will take care of it in next revision.

>>
>> qn = node->data;
>>
>> @@ -159,13 +200,96 @@ int qcom_icc_bcm_init(struct qcom_icc_bcm *bcm, struct device *dev)
>> }
>> EXPORT_SYMBOL_GPL(qcom_icc_bcm_init);
>>
>> +static bool bcm_needs_qos_proxy(struct qcom_icc_bcm *bcm)
>
> Although this part is not exported to the modules, I think it deserves
> some documentation. Either in the commit message or in the source
> file.
>

I am going to address this in V3.

>> +{
>> + int i;
>> +
>> + for (i = 0; i < bcm->num_nodes; i++)
>> + if (bcm->nodes[i]->qosbox)
>> + return true;
>> +
>> + return false;
>> +}
>> +
>> +static int enable_qos_deps(struct qcom_icc_provider *qp)
>> +{
>> + struct qcom_icc_bcm *bcm;
>> + bool keepalive;
>> + int ret, i;
>> +
>> + for (i = 0; i < qp->num_bcms; i++) {
>> + bcm = qp->bcms[i];
>> + if (bcm_needs_qos_proxy(bcm)) {
>> + keepalive = bcm->keepalive;
>> + bcm->keepalive = true;
>> +
>> + qcom_icc_bcm_voter_add(qp->voter, bcm);
>> + ret = qcom_icc_bcm_voter_commit(qp->voter);
>> +
>> + bcm->keepalive = keepalive;
>> +
>> + if (ret) {
>> + dev_err(qp->dev, "failed to vote BW to %s for QoS\n",
>> + bcm->name);
>> + return ret;
>> + }
>> + }
>> + }
>> +
>> + ret = clk_bulk_prepare_enable(qp->num_clks, qp->clks);
>> + if (ret)
>> + dev_err(qp->dev, "failed to enable clocks for QoS\n");
>> +
>> + return ret;
>> +}
>> +
>> +static void disable_qos_deps(struct qcom_icc_provider *qp)
>> +{
>> + struct qcom_icc_bcm *bcm;
>> + int i;
>> +
>> + clk_bulk_disable_unprepare(qp->num_clks, qp->clks);
>> +
>> + for (i = 0; i < qp->num_bcms; i++) {
>> + bcm = qp->bcms[i];
>> + if (bcm_needs_qos_proxy(bcm)) {
>> + qcom_icc_bcm_voter_add(qp->voter, bcm);
>> + qcom_icc_bcm_voter_commit(qp->voter);
>> + }
>> + }
>> +}
>> +
>> +static int qcom_icc_rpmh_configure_qos(struct qcom_icc_provider *qp)
>> +{
>> + struct qcom_icc_node *qnode;
>> + size_t i;
>> + int ret;
>> +
>> + ret = enable_qos_deps(qp);
>> + if (ret)
>> + return ret;
>> +
>> + for (i = 0; i < qp->num_nodes; i++) {
>> + qnode = qp->nodes[i];
>> + if (!qnode)
>> + continue;
>> +
>> + if (qnode->qosbox)
>> + qcom_icc_set_qos(qp, qnode);
>> + }
>> +
>> + disable_qos_deps(qp);
>> +
>> + return ret;
>> +}
>> +
>> int qcom_icc_rpmh_probe(struct platform_device *pdev)
>> {
>> + struct qcom_icc_node * const *qnodes, *qn;
>> const struct qcom_icc_desc *desc;
>> struct device *dev = &pdev->dev;
>> struct icc_onecell_data *data;
>> struct icc_provider *provider;
>> - struct qcom_icc_node * const *qnodes, *qn;
>> struct qcom_icc_provider *qp;
>> struct icc_node *node;
>> size_t num_nodes, i, j;
>> @@ -199,12 +323,35 @@ int qcom_icc_rpmh_probe(struct platform_device *pdev)
>>
>> qp->dev = dev;
>> qp->bcms = desc->bcms;
>> + qp->nodes = desc->nodes;
>> qp->num_bcms = desc->num_bcms;
>> + qp->num_nodes = desc->num_nodes;
>>
>> qp->voter = of_bcm_voter_get(qp->dev, NULL);
>> if (IS_ERR(qp->voter))
>> return PTR_ERR(qp->voter);
>>
>> + if (desc->config) {
>> + struct resource *res;
>> + void __iomem *base;
>> +
>> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> + if (!res)
>> + return -ENODEV;
>
> Having a working ICC even without QoS changes is still important. I'd
> suggest to warn the user here and continue probe, skipping QoS
> settings.
>

I am going to address this in V3.

>> +
>> + base = devm_ioremap(dev, res->start, resource_size(res));
>> + if (IS_ERR(base))
>> + return PTR_ERR(base);
>> +
>> + qp->regmap = devm_regmap_init_mmio(dev, base, desc->config);
>> + if (IS_ERR(qp->regmap))
>> + return PTR_ERR(qp->regmap);
>> + }
>> +
>> + qp->num_clks = devm_clk_bulk_get_all(qp->dev, &qp->clks);
>> + if (qp->num_clks < 0)
>> + return qp->num_clks;
>> +
>> for (i = 0; i < qp->num_bcms; i++)
>> qcom_icc_bcm_init(qp->bcms[i], dev);
>>
>> @@ -229,6 +376,10 @@ int qcom_icc_rpmh_probe(struct platform_device *pdev)
>> data->nodes[i] = node;
>> }
>>
>> + ret = qcom_icc_rpmh_configure_qos(qp);
>> + if (ret)
>> + goto err_remove_nodes;
>> +
>> ret = icc_provider_register(provider);
>> if (ret)
>> goto err_remove_nodes;
>> @@ -247,6 +398,7 @@ int qcom_icc_rpmh_probe(struct platform_device *pdev)
>> err_deregister_provider:
>> icc_provider_deregister(provider);
>> err_remove_nodes:
>> + clk_bulk_put_all(qp->num_clks, qp->clks);
>
> No!!! You should never manually free the resources that are handled by
> the devm_ functions. In rare cases it is really necessary for some
> reason, there exists a counterpart devm_free_something funciton.
>

Yeah, i will remove it in next revision.

>> icc_nodes_remove(provider);
>>
>> return ret;
>> @@ -258,6 +410,7 @@ void qcom_icc_rpmh_remove(struct platform_device *pdev)
>> struct qcom_icc_provider *qp = platform_get_drvdata(pdev);
>>
>> icc_provider_deregister(&qp->provider);
>> + clk_bulk_put_all(qp->num_clks, qp->clks);
>
> And here again.
>

Yeah, i will remove it in next revision.

>> icc_nodes_remove(&qp->provider);
>> }
>> EXPORT_SYMBOL_GPL(qcom_icc_rpmh_remove);
>> diff --git a/drivers/interconnect/qcom/icc-rpmh.h b/drivers/interconnect/qcom/icc-rpmh.h
>> index 2de29460e808..65cef156f212 100644
>> --- a/drivers/interconnect/qcom/icc-rpmh.h
>> +++ b/drivers/interconnect/qcom/icc-rpmh.h
>> @@ -1,12 +1,14 @@
>> /* SPDX-License-Identifier: GPL-2.0 */
>> /*
>> * Copyright (c) 2020, The Linux Foundation. All rights reserved.
>> + * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved.
>> */
>>
>> #ifndef __DRIVERS_INTERCONNECT_QCOM_ICC_RPMH_H__
>> #define __DRIVERS_INTERCONNECT_QCOM_ICC_RPMH_H__
>>
>> #include <dt-bindings/interconnect/qcom,icc.h>
>> +#include <linux/regmap.h>
>>
>> #define to_qcom_provider(_provider) \
>> container_of(_provider, struct qcom_icc_provider, provider)
>> @@ -18,6 +20,11 @@
>> * @bcms: list of bcms that maps to the provider
>> * @num_bcms: number of @bcms
>> * @voter: bcm voter targeted by this provider
>> + * @nodes: list of icc nodes that maps to the provider
>> + * @num_nodes: number of @nodes
>> + * @regmap: used for QoS, register access
>> + * @clks : clks required for register access
>> + * @num_clks: number of @clks
>> */
>> struct qcom_icc_provider {
>> struct icc_provider provider;
>> @@ -25,6 +32,11 @@ struct qcom_icc_provider {
>> struct qcom_icc_bcm * const *bcms;
>> size_t num_bcms;
>> struct bcm_voter *voter;
>> + struct qcom_icc_node * const *nodes;
>> + size_t num_nodes;
>> + struct regmap *regmap;
>> + struct clk_bulk_data *clks;
>> + int num_clks;
>
> Is it really necessary to store this in the global data? If I
> understand correctly, QoS is only programmed during the boot and is
> not to be reprogrammed later. Is my understanding correct?
>

qcom_icc_rpmh_configure_qos() can be invoked from outside of qcom_icc_rpmh_probe() in QuickBoot mode where *_probe does not happen.
so it will be easier to access this data if we keep it in global data when invoked outside of *_probe().

>> };
>>
>> /**
>> @@ -41,6 +53,23 @@ struct bcm_db {
>> u8 reserved;
>> };
>>
>> +/**
>> + * struct qcom_icc_qosbox - Qualcomm specific QoS config
>
> Why is it qosbox?
>

QOS box is the name used to describe the QOS policy override part of NIU HW in NOC.

>> + * @prio: priority value assigned to requests on the node
>> + * @urg_fwd: if set, master priority is used for requests.
>> + * @prio_fwd_disable: if set, master priority is ignored and NoC's default priority is used.
>> + * @num_ports: number of @ports
>> + * @port_offsets: qos register offsets
>> + */
>> +
>> +struct qcom_icc_qosbox {
>> + const u32 prio;
>> + const bool urg_fwd;
>> + const bool prio_fwd_disable;
>> + const u32 num_ports;
>> + const u32 port_offsets[] __counted_by(num_ports);
>> +};
>> +
>> #define MAX_LINKS 128
>> #define MAX_BCMS 64
>> #define MAX_BCM_PER_NODE 3
>> @@ -58,6 +87,7 @@ struct bcm_db {
>> * @max_peak: current max aggregate value of all peak bw requests
>> * @bcms: list of bcms associated with this logical node
>> * @num_bcms: num of @bcms
>> + * @qosbox: qos config data associated with node
>> */
>> struct qcom_icc_node {
>> const char *name;
>> @@ -70,6 +100,7 @@ struct qcom_icc_node {
>> u64 max_peak[QCOM_ICC_NUM_BUCKETS];
>> struct qcom_icc_bcm *bcms[MAX_BCM_PER_NODE];
>> size_t num_bcms;
>> + const struct qcom_icc_qosbox *qosbox;
>> };
>>
>> /**
>> @@ -114,6 +145,7 @@ struct qcom_icc_fabric {
>> };
>>
>> struct qcom_icc_desc {
>> + const struct regmap_config *config;
>> struct qcom_icc_node * const *nodes;
>> size_t num_nodes;
>> struct qcom_icc_bcm * const *bcms;
>> --
>> 2.17.1
>>
>>
>
>

Thanks,
Odelu